DE1479769A1 - Process for joining plastic parts by friction welding and plastic parts produced by deep-drawing processes to carry out this process - Google Patents

Description

Process for bonding plastic parts by means of precision tooth welding and Kunatatof parts produced in the deep-drawing process for the implementation of this process die The invention relates to a method for joining plastic parts Friction welding and on such Kunetetofftteile in a deep drawing process Also made of Kunatatofffilie and then to carry out the aa Priktiona welding process are sorborettot. e 8 has been known for a long time, plastic parts made by friction welding connect to. Thereby ßewühnlioh swei round parts made of thermoplastics are turned against each other rubbed on top of each other until there is a development of heat that makes the material plastic leaves. The belden parts are then pressed together at the sohweißatelle.

In the past, one essentially only has this priiction Applied to external thermoplastic injection-molded parts. Dan friction welding process namely has companion devices that aohon su with injected Kunatator parts Orhebllchen procedural difficulties and its application in from thermoplastic Plastic film thermoformed toilets have so far been practically impossible.

Such a major difficulty arises from the emergence of Crumbs of material when the plastic surfaces rub against each other. These crumbs of material migrate laterally when the two plastic surfaces are rubbed together get into the more or less cold remaining, adjacent to the welding point Areas where aie especially at the outer edge facing the welding point the su connecting parts can easily lead to one of the two parts is blasted, so in the longitudinal direction rice.

This already applies to parts injection-molded from thermoplastic material Occurring danger is naturally with those parts, the new thermoplastic isher Plastic sheeting is deep-drawn, very violently larger because, on the one hand, the wall thickness deep-drawn parts are much smaller than the wall thickness of injection-molded parts, and on the other hand, a long orientation of the structure (molecular structure) through the deep-drawing process of the plastic and therefore deep-drawn plastic parts are all the more powerful have preferred tendency to tear in the longitudinal direction, the more they are drawn are. In the case of thermoformed parts made of thermoplastic plastic film, however, still added the essential difficulty that is caused by the embrittlement of the plastic in deep drawing and in the subsequent disintegration, in particular floodplain dancing Form parts of the plastic sheet at the top of the cut edge Haarrlsee. Such hairline cracks are suitable, even with low stress on the edge area of the deep-drawn plate form starting points for larger cracks, since the Resistance to tear propagation due to the above-mentioned influence on the structure the Deep drawing process is very violent than the tear resistance of the material.

In contrast, a purpose of the invention is the known friction welding of thermoplastic plastic parts to the effect that the increased The risk of tearing in the vicinity of the welding point is eliminated. At the same time, there is a risk of tearing naoh Possibility to be so largely reduced that the friction welding not only for molded plastic parts is significantly improved, but even now not fully safe for the hot-dip drawing process on thermoplastics Plastic-made parts is applicable.

This is achieved by the invention in that during the friction welding the edge of at least one of the parts to be connected at least up to the melting temperature the material is heated.

This BrwErnen on the edge of at least one of the parts to be connected can, but does not have to result in additional welding within the scope of the invention lead directly to the edge. It is essential within the scope of the invention that the in at least one hand lying next to the actual welding point of the connecting parts is soft and pliable and thus the previous at Friction welding eliminates the unavoidable risk of friction.

If you want to do this in a hurry, you can do this by deep-drawing plastic film are made, you will expediently the cut edge, and swar its upper @arp edge, at least one of the connecting parts as to be heated Select border area.

In this way one aligns at the same time that also those at Awxchneldon hairline cracks arising from the plastic sheet are strung bsw. weld. The risk of tearing is then not eliminated during the friction welding itself, but also practically switched off fdr apUterhin. Acts on oneself. at the too connecting parts to those, one of which is more, perhaps even a lot more and the other less deeply sucked, then the edge area is appropriate the deeper part is heated.

The edge heating can also be directly related within the scope of the invention the friction heat-treating, namely by the fact that the to be heated Edge area during the friction reduction through friction on the other connecting surface Part is heated. You have the opportunity to duroh the desired heating Adjustment to control the Druokea applied in the edge area. One can for example control of the edge area so that only a melting of the edge area, but not pre-welding with other Kunatof parts occurs. Hiersu can warm the su Edge area under less pressure than the area to be welded on the other part to be connected are rubbed.

For some cases, especially when welding thin-walled ones deep-drawn Kunatatofftteile, is corner-wise, the risk of tearing is not alone actual edge area, but at all In the neighborhood of the To fix friction weld. This can be done according to the invention to the outside towards the areas to be welded and, if necessary, laterally to the edge area still connect areas in which the OWrtlSolwn of the parts to be connected in Distance to be taken. This creates enough space for the useful material trOws created and prevents these cracks in the plastic parts to be connected cause. Another major improvement in the method of the invention sikh still shows what is friction welding in at least two adjacent Areas, which are separated by an area in each case the surfaces of the connecting areas would be kept at a distance from each other * Ztv implementation of this process with parts made of plastic film in deep drawing process are made, the one of the au connecting parts with one above the prepared Friction weld area protruding edge be formed, the over the also over the friction welding area protruding edge of the other part engages, which both edge areas sillon formed from mutual rubbing surface contact be. The edge area d @ s one part, which reaches over the rarity of the other part, Already offers a remarkable protection for the overlapped edge, but Practice has shown that hard blows are already applied to the friction welding cables facing the opposite side Edge of deep-drawn Kunatatef partsauareichenMnaan, umRiaaabiaindieachweitatolls into it to evoke. Obnohla aehon is evidently made by daa priktionaschwoißen The deep-drawing process still has a significant impact on the tear strength of the material worsened. Due to the edge training of the toile to be connected gongs of the invention during the friction welding process, the desired heating of the edges of the overlapped Edge caused and thereby a heat treatment of the geatreokten Materiala bin to the PriktionaaohweiBatelle caused the suitable lot # oneaeite in the margin Eliminate existing hamstrings and, on the other hand, the original tear properties of the material.

Sikh has shown it to be particularly good when it comes to at least one of the two parts between the friction welding area and the edge area a resilient one Intermediate area trained fet. In this way, jsgliaho becomes wedge effect bois Priktionsschweißung switched off on the edge, and on the other hand leaves sioh the resilient Intermediate area from case to case according to the desired system pressure of the to the heating edge area.

Further features and advantages of the invention emerge from the fols Description of embodiments based on the drawing. It show: Liners thermoformed Container, glued or welded into the deodorant or floor in a conventional manner is@ 2 is a modified embodiment of a container with a conventional one Way glued or welded floor; a deep-drawn container, its Bottom or lid attached by friction welding in a method according to the invention iett FIG. 4 shows an enlarged sectional view of the friction weld ligur 3 $ a profile section through the edge of the container before attaching the lid or, bottom and pleur 6 a Scholft through a possibly modified yriktioneeohweiB-atelle after the discovery.

Figures 1 and 2 seigen a deep-drawn container 1, the at 2 a Widening of the son's edge. The conventionally welded or glued Lid 3 has a cutting edge 4.

The container 1 and the lid are attached to the two opposite edges 2 and 4 3 fine hairline cracks from the punching tool or the saw.

Theee Iluarrieae favor yin tearing on. Will beiepiels-WE186 such a container, as shown in Figure 1, etark burdened, so it tears at the hairline cracks, because by deep drawing the container 1 and dos Deokele 3 the luter tear resistance from this hairline from atark In the example in FIG. 2, the relationships are roughly the same.

The procedure and the formation of the su-connecting parts according to the Invention are shown schematically in FIG.

There is shown in the container 5 with a bottom part 6. For implementation During the welding process, the container is held in a receptacle 7. the The receptacle 7 is supported against an outwardly projecting one formed in the container wall Ring 8 off. Vm the container 5 during the Priktionaeehweieverganges against Yordrehon su secure, in the area of the ringsus running Yoraprunges 8 and do * darder located parts of the container wall ribs 9 be attached. The lid 6 is formed on its outer edge with a collar 10 reaching over the edge of the container 5, wherein the inner surface of the collar 10 is under slight tension against the son surface of the container 5 prou. The actual welding area lies in the area between the Container edge and the projection 8, as indicated at 11. The welding area should have a @onus between about 5 ° and 25 °.

Vie special aue figure 5 ereiohtlioh, has the auegeeohnittene Container on a cutting surface 12 at the front a Spitae 13. However, the deodorant 6 has at the assigned point. d. H. a radius 14 at the transition to the collar toe Friction welding process is therefore curved there from the tip 13 enter into raeohee softening of the material and just there at the most endangered point the rrie deriving from cutting or Aus @ tan @@ n.

In the context of the invention, it is particularly expedient if the hand don Deokela 6 within the edge collar 10 with an approximately cylindrical part 15 formed iat, which is opposite the deodorant collar 10 and with dieaem the rim of the container receiving bute forms. The height of the cover collar 10 can be smaller than the cylindrical inner surface 15 are held in order to then find the lid with automatic lid opening. The one at the end of the inner surface The radius 16 of the cover collar 10 is used to easily overcome bonfalle sw the tip 10, d. H. to make it easier to find the lid.

In order to carry out the friction aachweißa, as already mentioned above, the container 5 held by the support 7.

The lid 6 is rotated relative to the container 5. This takes effect A 17 and the wall of the cover 6. The support 17 is then opposite the support 7 gendre and under the action of springs or the like. Axially in the direction of the support 7 to pressed, so that in the actual welding area 10 1s previously ventimmed Contact pressure between the container 5 and the lid 6 is ersougt. The one from the Aaflago T7 axially S @ stroke exerted is also over the cylindrical cover part 15 and the cover collar 10 on the tip 13 and the parts adjacent to it, namely the cut surface 12 and the radius 18 of the container edge caused by the molding technique transfer. This joins the statute-finding in area 10 actual Friction welding process a ra @@ he frictional heating and @in softening of the material at the tip 13 in, which calibrate from there to the Sohneidfläohz 12 and if necessary also on the radiua 18, if the Deakel is adapted to the shape of the radius 18 is.

When friction welding are also in the area of the tip 13, the Sohneeidfläohe 12 and the radius 18 produced material crumbs and material pearls. Around So prevent these crumbs of material and white pearls from being finished ßegenatandee worsen and before everything suoh is not between the lid and Clamp the edge of the container and blow open at least one small area at the edge, d. H. to tear, lxt in the example shown on the edge of the tendon diameter 19 kept slightly larger than the body diameter 20.

This creates a room 21 that is suitable. Crumbs of material and To absorb beads of sweat. Between the cylindrical part 15 of the lid rimea and the edge of the container is another receptacle 22 for crumbs of material and welding beads be done, the tuber don Radius 18 to einwarta wanderno Dieoos xweit 22 can be created in that the material from the container edge 12, 13, 18 ago after the container wall sa greatly reduced.

In the example in FIG. 4, the cover 6 is designed in such a way that it is in its transition region 23 from the lid edge to the actual lid surface is a bulbous one Perm has and tek tu dü @ nt seim can. In this transition area 23 can then Dachshund 5 lids slightly against the boil. When welding in, the pressure on the stables plumb so low that no heating occurs or at least no heating is suitable lut, soften the material su. With the bead-like transition bar 23 forms the Lid 6 sima closure for the after aubes voratehanden Yoreprung 8 the container, so that there is an intake area 24 for crumbs of material and beads of sweat.

In FIG. 6 lof the cover collar 10 opposite Deokelrandbereich 25 formed somewhat undercut. This means that the radius is used 1B free at the edge of the container, but the Deokolabeohnitt 25 therefore has a fadernous effect Glissa, due to the softening of the tips 13, the cut surface 12 of the container edge ltdernd in engagement with the inner surface of the cover collar 10 @icht.

In the example in FIG. 6, the cover 6 is soldered without the closure boson 23 trained and therefore suitable for colobe applications without Sohuden in the Inaerw don container may fall bsw. the container is still on the opposite side is open and disregard it with a second lid shall be.

Allo reproduced in the beach description, the claims and the drawing Features of the subject of the application can be used for sloh alone or in any conceivable Combination essential for discovery.

Claims (17)

P a t e n t a n s p r ü c h e 1. Process for joining thermoplastic, plastic parts produced preferably by deep drawing by friction welding, characterized in that during the friction welding the edge at least one of the su connecting parts at least up to the melting temperature of the material is heated. 2. The method according to claim 1, for connecting by deep mices Parts made of plastic film, characterized in that the Edge region of the cut edge, namely its upper sharp edge, at least one of the parts to be connected. 3. The method according to claim 1 or 2, for connecting by deep drawing Parts made of plastic film, one of which is more and the other is drawn less deep, characterized in that the edge area of the deeper drawn part is heated. 4. The method according to any one of claims 1 - 3, characterized in that that the edge area to be heated during aee friction welding by friction is heated at the other tail to be connected. 5. The method according to claim 4, characterized in that the su orwdrmends Edge area under less pressure than the see area to be denoted is rubbed on the other part to be connected. 6. The method according to any one of claims 1 - 5, characterized in that that aioh outwards to the areas to be welded and laterally to the to connecting the heating edge areas in which the surfaces of the su Parts are kept at a distance. 7. The method according to any one of claims 1-6, characterized in that that the friction welding in at least swei adjacent areas is carried out, each separated by an area in which the Surfaces of the connecting parts are kept at a distance from each other. 8. Plastic parts produced in the deep-drawing process on the opposite side Connecting duroh friction welding in the process according to one of claims 1-7, thereby gekennseichnet that one (6) of the su connecting parts (5, 6) with an Uber the prepared friction welding area (11) facing edge (10, 15, 25) is formed is, the about the ebonfalls over the PriktionesohweiBbereioh (11) above hand (12, 13, 18) of the other toilet (5) grips, and the two edge areas see below mutual rubbing surface contact are formed. 9. Plastic parts nah Anspruoh 8, characterized in that on swisohen at least one (6) of the two toilets (5, 6) the friction welding area (11) and the hand area (10) a resilient intermediate area (25) is formed. 10. Plastic parts according to claim 8 or 9, one of which is deeper, for example as a container or the like, or other less deep, beiepialweise ale lid or base, is drawn, characterized in that the less deep-drawn Tail (6) on seineia Rnd with one over and (12, 13, 18) of the lower one Part (5) gripping collar. (10) is formed. 11. Plastic parts according to claim 10, characterized in that the springy intermediate area (25) on the side of the less deep-drawn toilet (6) is trained. 12 * Kunatato parts according to one of claims 8-11, characterized in that that in at least one of the two parts (5 <6) storage spaces (21, 22, 24) for the Crumbs of material and welding beads that occur during friction welding next to the Priktionaechwei8bereich (11), preferably to dease both sides and next to the hand area to be grown (12, 13, 18), preferably also has to be both Sides, are preformed. 13. Plastic parts according to one of the claims 8-12, characterized in that that the two parts (5, 6) in the friction welding area (11) with a tone of 50 to 25 ° are formed and the over don Frictionaaohweiabereioh (11) are in front Edge areas (10, 12, 1S, 25) of bridal parts (5, 6) in general cylindrical are formed, with the cylindrical area (12) of the one healing (5) encompassing edge regions (10, 15t 20) of the other part (6) one in the weanetlichen Form cylindrical grooves. 14. Plastic parts according to claim 9 and 13, characterized in that that the inner edge area of the receiving groove, designed as a resilient intermediate area is formed undercut. 15. Plastic parts according to claim 13, characterized in that duss the inner edge region (15, 25) of the receiving groove at a greater height than the cylindrical ones Edge area of the other hiles (5) gripping collar (10) is formed. 16. Plastic parts according to claim 13, characterized in that the itand area of the one toilet (5) reaching into the receiving groove with a tip (13) and a winch inwardly adjoining this radius (18) and this edge area overlapping collar (10) is formed at its entrance with a radius (16). 17. Plastic parts according to claim 12 and 13, characterized thereby, that the edge area of one part (5), which is excluded from the receiving groove, is a son's oath (19) has larger dimensions than the body diameter (20). 1b. Plastic parts according to claim 12, characterized in that the one fitoll (6) is formed on all covers and in his Transition area (23) from the edge of the lid to the lid surface in a bead-like shape with a heavily thinned and thickness is designed to easily lid against the wall of the counterpart (5).